Background

A 250,000 barrel above ground storage tank (tank # 250-2) was dislodged, lifted and damaged in flooding associated with Hurricane Katrina. At the time, the tank contained 65,000 barrels of mixed crude oil, and released approximately 25,110 barrels (1,050,000 gallons). The released oil has impacted approximately 1700 homes in an adjacent residential neighborhood; an area of about one square mile. Several canals have also been impacted: the 20 Arpent; the 40 Arpent; the Meraux; the Corinnes; the Delarond; and, various unnamed interceptor canals.

As part of the Hurricane Katrina Response, and pursuant to FEMA Mission Assignment, US EPA and the US Coast Guard (USCG) have responded to an oil spill from the Murphy Oil facility. US EPA and the USCG have agreed to divide responsibility for overseeing Murphy’s cleanup of the spill. The USCG is overseeing Murphy's removal of free oil in the canals, tank farm containment area, neighborhood streets and storm drains. To date, approximately 18,000 barrels of oil have been recovered. US EPA is working closely with the Louisiana Department of Environmental Quality (LDEQ) in overseeing Murphy's cleanup of oil in residential areas accessible to the public (e.g., parks, school yards, roads, highway median strips, sidewalks).

US EPA is also overseeing Murphy’s ongoing sampling activities of residential and other properties. Ten percent of the samples Murphy collects are split, and US EPA sends the split samples for independent analysis. Thus far, Murphy has collected 8808 sediment samples from 5440 properties. Of the 8808 sediment samples collected, US EPA has sent 909 split samples for separate analyses. US EPA has received, evaluated and is posting the results of the first 881 samples.

Polycyclic Aromatic Hydrocarbons (PAHs)

PAHs, such as benzo(a)pyrene, are commonly found in fuel oils and crude oil, and were detected above LDEQ screening levels for residential soil in approximately 2.5% of the sediment samples split with Murphy. The oily nature of some of the samples resulted in elevated detection limits. Thus, while some of the other samples may be reported as non-detect, the actual levels of PAHs may also be above the screening levels.

Diesel and Oil Range Organic Chemicals

Levels of diesel range organic chemicals exceeded the LDEQ screening levels for residential soil in approximately 29% of the samples; whereas, levels of oil range organic chemicals exceeded the residential screening levels in approximately 21% of the samples.

Arsenic

The results of inorganic analyses are available for a limited number of the sediment samples collected. Two samples exceeded LDEQ’s screening level of 12 mg/kg for arsenic. One sample contained 12.5 mg/kg arsenic, and the other contained 13.1 mg/kg arsenic.

Data Evaluation - Confirmatory Sampling

Pursuant to FEMA Mission Assignment, US EPA is overseeing Murphy Oil's clean up of residential properties where soil contamination exceeds LDEQ's Risk Evaluation/Corrective Action Program (RECAP) Management Option 1 Soil Standards (PDF, 10 pp., 60 KB, About PDF) for chemicals associated with the spill. Additional soil samples are being collected at each property to confirm that the RECAP standards for phenanthrene,
fluoranthene, pyrene, chrysene, naphthalene and diesel and oil range organic chemicals have been met. Following the same protocol used in characterizing the extent of contamination, ten percent of the confirmatory samples Murphy collects are split, and US EPA sends the split samples for independent analysis. US EPA has received, evaluated and is posting the results of the first 91 samples.

The level of diesel range organics in a confirmatory sample collected on July 14th exceeded the RECAP standard of 650 ppm. The same location was resampled on August 31st and the levels of all spill related compounds detected were below their respective RECAP standards. Benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene and dibenz (a,h) anthracene were also detected in the August 31st sample sample at 4,200 ug/kg, 4,000 ug/kg, 2,900 ug/kg and 410 ug/kg, respectively. Although the levels of these compounds detected in the August 31st sample exceed their RECAP values, the levels falls within a risk range, of 1 in 1,000,000 to 1 in 10,000 risk of an individual developing cancer over a lifetime from exposure to those concentrations, which USEPA has found acceptable in other contexts. (See Enviromapper stations 24267 and 24526)

Recommendations

In the short-term, residents returning to the area should avoid direct contact with the crude oil contaminated sediments. These compounds can pose a skin irritation problem if they get onto bare or broken skin. Skin contact with crude oils for short periods may cause itchy, red, sore, or peeling skin.

The Louisiana Department of Health and Hospitals (LDHHs) has developed a fact sheet, titled “Extra Precautions for Entering Oil Contaminated Properties in St. Bernard Parish,” that recommends the following safety precautions for persons entering and/or cleaning properties in St. Bernard Parish impacted by the Murphy Oil Spill:

Protect your skin from contacting oil

Use oil resistant gloves

Keep arms and legs covered

Wear coveralls or clothing that can be discarded

If you get oil on skin, wash well with soap & water

Open doors and windows to ventilate the oil-contaminated property

Be careful not to bring oil-contamination to other places

Wear boot covers or leave work boots at the oil-contaminated property.

Do not track oil or oily sediments into your car or truck

Do not take items with oil to other locations that might contaminate others

Do not wash clothes worn in the oil spill area with family laundry

Children and pets should not enter the oil contaminated area

These recommendations are consistent with previous recommendations from
US EPA.